The U.S. Food and Drug Administration (FDA) approved Amgen’s supplemental Biologic License Application (sBLA) for Blincyto (blinatumomab) to treat adults and children with B-cell precursor acute lymphoblastic leukemia (ALL) under specific circumstances.
The U.S. Food and Drug Administration (FDA) approved Amgen’s supplemental Biologic License Application (sBLA) for Blincyto (blinatumomab) to treat adults and children with B-cell precursor acute lymphoblastic leukemia (ALL) under specific circumstances.
Those circumstances are in patients in first or second complete remission with minimal residual disease (MRD) greater than or equal to 0.1 percent. What “minimal residual disease” means is that the presence of the disease is only seen under a microscope or via newer molecular tests. These patients have an increased risk of relapse.
The company noted that for this indication, the drug was approved under an accelerated approval process based on MRD response rate and hematological relapse-free survival (RFS). As a result, continued approval for the indication could be rescinded if confirmatory trials don’t verify the clinical benefit.
In its related studies, four out of five patients who were tested to have residual ALL and received the drug showed no indications of the disease after a single cycle of Blincyto.
At this point, Blincyto is the first and only therapy approved by the FDA for MRD. The drug is a bispecific CD19-directed CD3 T-cell engager (BiTE) immunotherapy. It binds to CD19 on the surface of B-lineage originating cells and CD3 that is expressed on T-cell surfaces. The FDA gave the drug breakthrough therapy and priority review designations in 2014. It is approved in the U.S. to treat relapsed or refractory B-cell precursor ALL in adults and children, and now the new indication. It also received conditional marketing authorization in Europe in November 2015 for adults with Philadelphia chromosome-negative (Ph-) relapsed or refractory B-cell precursor ALL.
“Until today, no therapy has been satisfactory in eradicating MRD or approved specifically to treat this high-risk patient population,” said David Reese, Amgen’s senior vice president of Translational Sciences and Oncology, in a statement. “This approval not only supports the use of Blincyto earlier in the ALL treatment continuum, but represents a paradigm shift in the management of ALL.”
Approximately 5,960 people in the U.S. are diagnosed with ALL each year, and about 1,470 die from it annually, according to the National Cancer Institute.
Blincyto has an average wholesale price of approximately $173,000. In 2017, total sales were $175 million.
“This is the first FDA-approved treatment for patients with MRD-positive ALL,” stated Richard Pazdur, director of the FDA’s Oncology Center of Excellence and acting director of the Office of Hematology and Oncology Products in the FDA’s Center for Drug Evaluation and Research. “Because patients who have MRD are more likely to relapse, having a treatment option that eliminates even very low amounts of residual leukemia cells may help keep the cancer in remission longer. We look forward to furthering our understanding about the reduction in MRD after treatment with Blincyto. Studies are being conducted to assess how Blincyto affects long-term survival outcomes in patients with MRD.”
The FDA appears to have some concerns over safety issues. The advisory committee voted 8 to 4 in its recommendations, due to concerns over side effects. The drug carries a boxed warning that some patients had issues with low blood pressure and difficulty breathing, or cytokine release syndrome, at the beginning of treatment, as well as difficulty with thinking or other central nervous system side effects. There are also serious risks of infections, effects on driving ability, pancreatitis, and problems with preparation and administration errors because the instructions for treatment must be followed closely.
